I'm starting to observe with my recently acquired C5+. I'd love to hear owner experiences regarding lunar and planetary observing, what ep's, diagonals you use etc.
must say the star test is very similar each side of focus, impressive for an sct.

In order of use, a Meade 5000 20mm SWA, a Vixen 8-24mm zoom, a Meade 2x Barlow and a Meade 6mm ortho. Also an f/6.3 corrector-reducer sees a good deal of use.

The C5 is a great scope. Mine is riding a Nexstar 6 SE mount and sees nearly as much use as my CPC1100. Last summer I was in Nevada at 4500' observing with the owner of a Televue 86mm f/7 refractor. He had two TV zooms, one going down to 3 or 4mm and we tried both on the C5. He glued himself to the C5 and when I made a polite inquiry he pointed me at his TV and stayed on the C5 for an hour. I won't say the C5 was better than his $2300 refractor (why start arguements). But he said, "I had no idea that such a small cat could perform so well".

must say the star test is very similar each side of focus, impressive for an sct.

Thanks!Mike

I don't have the C5+ but do have the White tube C5 which I believe is the same vintage. Yes, the star test is very very good. Probably one of the best SCT star tests I have seen. I use mine with just a Telrad, although I do have a 50mm finder that fits it.Typically I only use it in the back yard for short sessions, and I carry it in a soft sided cooler bag for family vacations and camping trips. I use a 1.25 Orion dialectric diagonal, and various 1.25 eyepieces.The little C5 compares quite well to a good 4 inch refractor, as far as resolution and definition are considered. Although I have been tempted several times by the C6, I find that the ultra portability of the C5 and the first rate optics prevent me from selling it.

Last summer I was in Nevada at 4500' observing with the owner of a Televue 86mm f/7 refractor. He had two TV zooms, one going down to 3 or 4mm and we tried both on the C5. He glued himself to the C5 and when I made a polite inquiry he pointed me at his TV and stayed on the C5 for an hour. I won't say the C5 was better than his $2300 refractor (why start arguements). But he said, "I had no idea that such a small cat could perform so well".

I've had similar experiences. The C5 is often under rated, and under appreciated.
The 5 inches of aperture in a tube the size of a can of coffee is one of amateur astronomy's best kept secrets.

I have the white tube C5 spotter as well and all though I have not used it in some time I am reluctant to sell it because of its great optics and such small size. I can fit it with a diagonal, a few eyepieces and my rigel RDF in a small bag and be off observing in a jiffy. It does need a fairly solid mount however. I use mine on a Super Polaris mount which takes up a little more space unfortunately.

While I tend to not use anything but my C14 for planets anymore, I have compared the planetary performance of the C5 to many scopes over the years and it is a better planetary scope than many people (can you say "Refractor?") would believe.

The view is to me only oh so very slighly less contrasty than in a 4" APO, but the image is so much brighter that it makes up for the difference.

I use a Meade Prism. I have used a Tak prism on it in the past, but honestly I could not really see any meaningful difference and I hated the nylon compression ring in the Tak, so went back to the Meade prism, which appears to be of reasonable quality.

I tend to use a variety of eyepeices in it, but mostly 11mm Plossl and Meade 8.8 UWA for planets.

For the moon, I can go to the 7mm T6 Nagler.

The C5 does very well on Saturn, showing the primary rings and Cassini easily but the Crepe is difficult except at very low powers.

Mars will show the polar cap almost always, and you can see albedo features on the disk, so you know that there are details, but the contrast is not high enough for much resolution.

Jupiter will show all of the larger details easily but festoons are a bit out of reach unless they are quite pronounced. Shadow transits are excellent in the C5, 100% as good as in the best 4" APOs I have owned, but these features start with very high contrast, so they still look very black in the C5. The disk of the moons that made them will not really be visible when they are in front of the Jovian disk, and you won't likely ever see any ovals that are not at least 3 or 4 arc seconds in diameter, on Jupiter but these are really a bit out of the reach of small apertures unless the observer has excellent contrast sensitivity.

GRS is pretty easy, as are the major belts and even some structure in the belts from time to time.

The moon to me is also as good in the C5 as in my 4" refractors. Again, much of the detail on the moon starts with sufficient contrast (shadow detail) that it still looks great in the C5, and some of the finer detail like the structure of the Triesnecker Rille system stands out as well as in a 4" APO because the resolution is slighly better and the added brightness allows a bit more magnification which helps with the smallest angular detail.

But for the faintest possible detail I think a 4" refractor could show a bit more, but only a bit. Sometimes a festoon would be hinted at in my 4" APO and not be visible at all in the C5. Of course these festoons will usually be easy in a large scope at just about any power, but they can be a challange for a good APO, and just out of reach of a C5. The contrast is very low to start with, and the C5 just looses a bit to much to reach into that kind of large, low contrast detail. This is the weak point of the C5. Large, very low contrast structure like festoons will be just out of reach.

In summary, a lot of 4" and smaller refractors have come and gone but the C5 remains. Not that it is a better plantery scope, but it is good enough to provide some decent small aperture observing, and I didn't like keeping so much money tied up in little refractors.

But neither the C5 or a 4" (or even a 6") APO would not be my first choice for a planetary scope.

Still, it is amazing how much you can see with a C5.

I recently put my Binoviewr on my C5. Was a lot of fun for low power observing. I was able to get a wider true field than when using the binoviewer in my 6" APO!

So you can see almost as much as with a 4" APO if your scope has good optics. Only the lowest contrast detail will escape you, and since a lot of this detail is not visible in any small aperture, you aren't missing much as compared to a lot of other small scopes.

I am not one of those people that recommends using 50x per inch. I find that past an exit pupil of about 1.1x per millimeter, I can make the image bigger, but not really better. I see pretty much 100% of the detail visible in a given scope at about this exit pupil size for planets (the moon I go a bit higher because it is bright).

The 8.8 gives about 160x in the C5, but I actaully find this to be OK, but the step to the 7mm just makes the image to dim and grainy to me. That is around 200x, and the exit pupil is so small that I start to loose the lowest contrast details.

So, this is me in my own scopes. I find little value in going over about between 1.1x per millimeter of aperture, though I can go to about 1.3x in the 6" APO and even 1.5x on Jupiter (it has a much higher percentage of light transmission than my other scopes) but I don't think I see any new detail in that scope at over about 1.3x per millimeter.

The 8.8 itself is I think a bit below par in terms of light transmission vs modern designs like the T5 and T6 Naglers, but it is very sharp.

But the main reason I use it is simple. I don't have anything else close to that focal length. LOL.

Again, I don't use these little telescopes for planets. The experience simply isn't very rewarding for me, but the C5 I think does better than many people would believe. As I mentioned, I have had a string of 4" refractors and I am not saying that the C5 is a better planetary scope, but at the same time, I don't feel that is is so inferrior that I would rather keep a 4" APO around that would not get used for planets anyway. So, not quite as good as a 4" APO, but close enough that I don't feel that I am missing much.

But if I want to do planetary observing, I grab my C14. Once you have spent 4 or 5 years obsevring planets with a decent quality large aperture scope, it really kind of spoils you.

Hope this answered your question. I use the 8.8 because it gives a good result and provides the right amount of magnification for me in terms of getting what I feel is the best potential from the scope. I can make the image bigger, but I just don't feel that it gets any better past this.

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As a C5+ owner, I like this thread! I have always felt this scope is way better than most who haven't used it would expect it to be. So....

Everything Eddgie said +1.

And, I will add the following: My favorite planetary eyepiece is either my 20mm Ultrascopic with TV 2.5x barlow (8mm effective focal length) for planets, or my 7mm TMB for the moon (some ghosting on the planets). Stock diagonal. I like larger apertures for planetary work, but this scope does well for it's size. Alas, I have no "premium" wide field glass.

I use mine mounted on an lx200 field tripod and it is two piece grab & go. A quick polar alignment and I have 9 volt tracking (no cords or big batteries) that is dead on at 200x.

The focuser is so smooth is it almost like the 10:1 on a two speed moonlight, and being a relatively light 5" primary there is zero image shift (unlike my 8" lx200). Really amazes people who have never used the C5+ before.

I know you specifically asked about Lunar and Planetary, but if you will allow a slight digression I would like to add that it is also a great performer on the brighter globs, planetary nebulae, and emmission nebulae. Double stars and open clusters are waiting in abundance, and with the F6.3 reducer/corrector some wider field targets are great.

I would have to have a very good reason to part with this little scope.

My C5+ was a chance to discover the moon again. It does a superb job on planets- if the seeing is good the detail just leaps out. I think my most useful eyepiece has been a 12.5mm plossl- lots of light with an extremely sharp image. 26mm gives a very bright and sharp wide field image.

After collimating with a 3mm eyepiece, the image is perfectly collimated at any practical viewing magnification.

I strongly recommend getting a dielectric diagonal- the difference is huge. No one starts making those unless the substrate is really good, so they perform well.

I have a pending experiment to try the Starizona f/7.5 flattener-corrector with it. The 2" back needed fit it can just be installed and miss the focus knob.

Make sure you try a 40mm ep on the Pleiades. We're talking diamonds on velvet- get to double cluster, also.

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I love my little C5 for it's ultra portable size.I use it on an AZ3 mount, that I have a love hate relationship with. I love the fact that it's so light weight that I can pick it up in one hand and put it in the back yard in a few seconds.I hate that it has a friction altitude adjustment rather than a balanced altitude adjustment.I hope to upgrade the mount soon.

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I was not using the C5 much, but after trying some binoviewers on it a couple of weeks ago, it has rekindled my intrest in using the little scope.

If I do, I am considering getting a similar mount to the one you have yours on. Thanks for the pic showing how it look.

I have a Polaris and like tracking, but for Binoviewers, I would most likely just do general sweeping and the Polaris has some clearance issues that have become more evident when using the binoviewers.

I need to research these mounts. Your picture gives the impression that it may meed my needs quite well.

I've compared my C-5 side by side with my XT12i. Looking at Saturn the XT12i was like HD TV over non-HD; better but not SO much better that I felt cheated not having it. Naturally the XT12i showed dimmer moons and background stars than the C-5 but the rings and cloud bands themselves had the same "whirled & grooved" appearance in both scopes; only ever so slightly sharper in the XT12i.

What really make the C-5 great is it's almost unique combination of capability and portability. Mine is a regular passenger when I take my Cub Scout son camping and believe me; if there was anything lacking in the view of Saturn don't tell the hundred-odd Cub Scouts and their sisters who were jumping up and down for "another look" (so were some of the parents).

I've bought one of the Stanley "Fat Max" tool boxes. It offers some degree of water resistance and is sturdy enough to double as an observing seat or step. In it I can pack everything save the tripod; the C-5, two diagonals (right angle & corrected view), a solar filter, a full selection of color and ND 1.25" filters, extra batteries, red light, AC & DC power jacks, a simple red-dot finder (bright enough for daylight use), along with 10+ eyepieces and barlows. Each accessory is packed in its own plastic case (tackle boxes, closet organizers, pencil boxes, etc.) so I can safely have out what I'll be using and free the Fat Max up for "ergonomic" purposes. I call it my observatory in a box.

It is a SUPER little scope and, even though my XT12i is my quick roll-out at home, I would never willingly part with my C-5.

Well, I had both a C5 and a 127 MCT at one time, but sold the 127 MCT (I just liked the wider field of the C5) but then sold the C5 too.

But I came to regret it. As I mentioned earlier, I rarely used to use the C5, but after a bunch of big, heavy 4" APOs that took more mount and didn't provide as bright a view, I started missing the C5 so I bought another one and every time I think of selling it, I remind myself that there really isn't any competition in the small scope market that would give me the same bright views of the C5.

Even the sub-4" scopes to me are not easier to set up because below a certian size, the mount starts to be more effort than the scope, and that is the case with the C5 vs 80mm refractors.

And this has been my message for a decade now.. Where refractors really excel is their ability to do a wide field. At the center of the field, it is all to easy to get better performance simply by using a slighly larger reflector.

And back to the OPs question, I find that just about any target that will fit into the field of the C5 will be a bit brighter and more detailed than the 4" refractors I owned. Some of the 80mm refractors seemed to struggle even to show the four stars of the Trapezium with enough brilliance to make them special.

But for the C5, all of these targets are more satisfying if it fits into the field.

And the performance on planets and the moon is not so different as the "Big Central Obstruction is bad" crowd would have us to believe. Yes there is a penalty, but it is a subtle one. Overall, the differnce between planetary and lunar views in the C5 is not the same, but similar enough that I find it to be fine for quick looks. For the most serious planetary observing though, I would not use even the best 4" APO. I tried it and just could not see enough to make it worth my time and the same is true with the C5.

But if you want a quick look, or something you can take out birding or camping, the C5 is better on most things, and almost just as good on a few things.

And since I have been binoviewing the C5, it has made me want to use the scope again.

Night before last, I had the C5 out and with binos and a pair of 24mm Eyepieces, I was shocked at how superb the Orion Nebula appeared. It was reallyIt stunning. It was large and bright and showed a lot of structure and extension.

Making me look at the C5 in a whole new light. Far more fun to use with binos than with mono, and because it really is a scope that is optimized for 1.25" use, you don't feel like you are giving up any true field. If you were going to use them with a 24mm Panoptic or something anyway, then you are getting close to the same size field with the Binos as you would in mono.

And this lets me get a wider true field in the C5 than I can get in my 6" APO because with that scope, I need to use a glass path corrector which makes the focal lenght 1800mm. Hmmmm.

Anyway, I do love my C5 and perhaps now that I am binoviewing more, it will get used more.

I really like the views the C-5 provides and the portability is terrific, much more than my other refractors (the only other 5" ota I have which is ok on the Voyager is my ST120 and I use that one especially for white light solar with a Baader film filter, and super wide-field viewing, but I prefer the C-5 for planets/moon). I love being able to just grab the C-5 setup and head out the door for a spontaneous session with the little cat. Mine came with the top adapter plate for adding a camera, etc. I just pick it up with that as an ota handle. I still have the original eq. mt. with wedge but the Voyager is just so much handier and I star-hop most of the time anyway.

The C-5 works well with the Voyager mt. with extension post. I like to use vibration pads with the original tripod. With the addition of a binoviewer it offers even more head/eyepiece access space for zenith viewing. I just have the WO binos now (wanted to try out binoviewing first to be sure I was able to merge the view, liked it, etc.) but have found for me they are really the best improvement for the views of moon/planets with many of my scopes. I see details much better and the image seems larger and easier to study -- more comfortable viewing certainly. I wish I'd tried them sooner! For my eyesight the binos are better help in seeing details than loads of other mono-vision eyepieces...but those come in handy with other scope combinations.

Glad to see so many enjoying their C-5's! It's great to just get out and view! I just need less rain. ---Maya